A kind of self-adaptive intelligent breathing ultraviolet protection knitted fabric and its preparation method

Abstract

The present invention belongs to the technical field of functional fabrics and relates to an adaptive intelligent breathing UV protection knitted fabric and a preparation method thereof. The adaptive intelligent breathing UV protection knitted fabric includes a region A woven from light-responsive yarns; the length of the light-responsive yarns changes with the intensity of ultraviolet light, thereby causing the tissue structure of region A to change with the intensity of ultraviolet light. When the ultraviolet light intensity is less than a threshold value, the tissue structure of region A is a mesh structure; when the ultraviolet light intensity is greater than or equal to the threshold value, the tissue structure of region A is a compact structure; its preparation method is as follows: during weaving, non-light-responsive yarns and light-responsive yarns are used to weave through a weft knitting machine or a warp knitting machine until the knitting length reaches the requirement, thereby obtaining an adaptive intelligent breathing UV protection knitted fabric. The present invention can autonomously adjust the mesh size according to the change in ultraviolet light intensity, thereby improving the air permeability and wearing comfort of the knitted fabric.

Description

Technical Field

[0001] The present invention belongs to the technical field of functional fabrics and relates to an adaptive intelligent breathing ultraviolet protection knitted fabric and a preparation method thereof. Background Art

[0002] Excessive ultraviolet and other harmful light can cause photochemical reactions, causing varying degrees of harm to the human body (skin or immune system) and objects. Therefore, people have a stronger awareness of ultraviolet protection and pay more and more attention to the ultraviolet protection function of fabrics.

[0003] Traditional UV-protective fabrics are fabrics that are composited with UV-resistant coatings, modified with grafting, or with the addition of UV-resistant chemicals. For example, patent application CN103835140A applies a UV-resistant coating to the fabric surface. Patent application CN116005335A weaves semi-gloss recycled polyester DTY and stretch polyester BEY into a greige fabric, which is then dyed with an anti-UV additive. Patent application CN114737385A grafts a UV absorber onto polyester fabric to produce UV-resistant fabric. Patent application CN116288791A uses titanium dioxide as a UV-resistant additive by adding it to the yarn during the slicing stage. However, these traditional UV-protective fabrics have the disadvantage that their mesh size is fixed and cannot be adjusted according to changes in UV light intensity. This, in turn, makes it impossible to adjust the fabric's breathability, which affects its wearer comfort. Therefore, fabrics with mesh sizes that change with UV light intensity have both application value and research significance.

[0004] Currently, there is no knitted fabric in the prior art whose mesh size changes with the intensity of ultraviolet light. There are only knitted fabrics that respond to other stimuli (such as humidity), but they are not suitable for ultraviolet light.

[0005] For example, patent application CN115852570A weft-knits microporous polyester / diacetate side-by-side composite yarns to create a moisture-responsive knitted fabric. The modified polyester yarn has a microporous surface structure, which increases the evaporation area and improves quick-drying properties. The difference in moisture regain between the modified polyester yarn and the diacetate yarn is significant. When the composite fabric encounters moisture, the size of the fabric loops and grain changes significantly, and the pores between the original side-by-side polyester and diacetate yarns increase. However, this type of knitted fabric that responds to humidity is not suitable for ultraviolet light. The reasons are: first, the response principles of moisture and ultraviolet light are different. The microporous structure of the yarn and the side-by-side arrangement of the yarn cannot absorb ultraviolet light, and the energy of ultraviolet light cannot be converted into yarn deformation; second, this type of weft knitted fabric is a single structure. After responding to external stimuli, the gaps between the yarns increase, rather than the gap changes caused by changes in mesh size. Even if the yarns of this weft knitted fabric are simply replaced with light-responsive yarns, the mesh size cannot be changed in response to light stimulation.

[0006] For example, patent application CN112869948A discloses an intelligent, moisture-responsive, compact fabric comprising compact fibers that shrink upon contact with liquid or moisture. These compact fibers are formed by stretching hydrogel fibers wet-wise by 0.5-50 times and then drying them. However, this moisture-responsive compact fabric is also unsuitable for UV light. First, the response principles of water-based liquids and UV light differ. Neither wet nor dry hydrogel fibers absorb UV light and cannot convert UV light energy into yarn deformation. Second, this moisture-responsive compact fabric is a tightly woven fabric constructed from moisture-responsive yarns. This can only shrink the fiber mesh, but cannot achieve selective partial shrinkage or localized mesh size changes. Simply replacing the compact fibers in this moisture-responsive compact fabric with light-responsive yarns will also fail to achieve mesh size changes upon light stimulation.

[0007] Therefore, it is necessary to combine a unique structural design to develop an adaptive intelligent breathing UV protective knitted fabric that can autonomously adjust the mesh size according to changes in UV light intensity, thereby improving the air permeability and wearing comfort of the knitted fabric. Summary of the Invention

[0008] The purpose of the present invention is to solve the problems existing in the prior art and provide an adaptive intelligent breathing ultraviolet protection knitted fabric and a preparation method thereof.

[0009] In order to achieve the above object, the technical solution adopted by the present invention is as follows:

[0010] An adaptive intelligent breathing UV protective knitted fabric includes an area A, which is an area woven by light-responsive yarns; the length of the light-responsive yarns changes with the intensity of ultraviolet light (wavelength range of 275-400nm) (e.g. Figure 1 and Figure 10 As shown in the figure, the structure of region A changes with the intensity of ultraviolet light. When the intensity of ultraviolet light is less than the threshold, the structure of region A is a mesh structure (i.e., adjacent yarns are not closely arranged and there are certain holes); when the intensity of ultraviolet light is greater than or equal to the threshold, the structure of region A is a compact structure (i.e., adjacent yarns are closely arranged and there are no gaps between them). The threshold value range is 125-225 mW / m 2 .

[0011] As the preferred technical solution:

[0012] As described above, in an adaptive intelligent breathing UV protective knitted fabric, in the mesh structure, the driving tension between the light-responsive yarn and the surrounding coils is not higher than 30 cN (preferably ≤25 cN); when the light-responsive yarn does not respond, the fabric is a mesh structure, the internal stress between the yarns is balanced, and remains stationary; when the light-responsive yarn responds, its mesh structure becomes a tight structure; the present invention limits the driving tension between the light-responsive yarn and the surrounding coils because the driving force of the light-responsive yarn is 30 cN. If the driving tension is too large, the light-responsive yarn will have difficulty contracting under high-intensity ultraviolet light irradiation, and the mesh cannot be closed.

[0013] As described above, an adaptive intelligent breathing UV protective knitted fabric ensures that the photoresponsive yarn can shrink under high-intensity UV light irradiation, and the mesh size and the shrinkage of the photoresponsive yarn cooperate with each other, so that when the UV light intensity changes from less than a threshold value to greater than or equal to a threshold value, the tissue structure of area A changes from a mesh structure to a tight structure; specifically, the present invention controls the mesh diameter or equivalent circular diameter of the mesh structure to be 1-5 mm; when the UV light intensity changes from less than a threshold value to greater than or equal to a threshold value, the length of the photoresponsive yarn is shortened by 5%-50%.

[0014] As described above, in an adaptive intelligent breathing UV protective knitted fabric, the shrinkage performance of the light-responsive yarn is determined by the fineness of the light-responsive yarn and the material of the light-responsive yarn; specifically, the present invention controls the fineness of the light-responsive yarn to be 20-100D when the ultraviolet light intensity is less than a threshold value; the light-responsive yarn is one or more of a photoresponsive liquid crystal elastomer yarn, Mxene / PDMS yarn, and a shape memory polymer (SMP) yarn.

[0015] Ordinary liquid crystal elastomer yarns are thermoresponsive liquid crystal elastomer yarns. When the temperature reaches the phase transition temperature, the liquid crystal units in the fiber change from an ordered phase to a disordered phase, which is manifested macroscopically as the contraction of the yarn. Photoresponsive liquid crystal elastomer yarns can be obtained by adding a photothermal conversion material (which absorbs light energy and converts it into heat energy) to the thermoresponsive liquid crystal elastomer yarn. When a light source is irradiated on the yarn doped with the photothermal conversion material, the photothermal conversion material absorbs light energy and converts it into heat energy, thereby driving the photoresponsive liquid crystal elastomer yarn. Currently available photoresponsive liquid crystal elastomer yarns include CNT / LCE yarns (made by mixing CNTs into LCE yarns), gold nanorods (AuNRs)@LCE yarns (made by mixing gold nanorods into LCE yarns), and PDA@MXene / LCE yarns (made by coating polydopamine (PDA)-modified MXene ink on the surface of LCE yarns).

[0016] The MXene / PDMS yarn is half MXene and the other half PDMS, which is a yarn already disclosed in the prior art;

[0017] RGO@HHF yarn is a yarn that has been disclosed in the prior art;

[0018] The shape memory polymer yarn is a yarn already known in the prior art.

[0019] As described above, in the adaptive intelligent breathing UV protective knitted fabric, the area other than area A is area B, and area B is an area woven from non-light-responsive yarns, and the tissue structure of area B is a compact structure.

[0020] If all areas of the fabric are area A, when the UV light intensity is high, the fabric as a whole will shrink, sticking close to the human body, and even feel tight and uncomfortable; if part of the fabric is area A and the other part is area B, when the UV light intensity is high, the fabric will only partially shrink and will not cause discomfort to the human body; area B can both protect against UV rays and have space margin to provide light-responsive yarn contraction.

[0021] For the above-mentioned adaptive intelligent breathing UV protection knitted fabric, when the UV light intensity is less than the threshold value, the distribution density of area A in the entire UV protection knitted fabric is 10 4 -12×10 4 pcs / m 2 ; When the UV light intensity is less than the threshold, area A is a mesh structure, area B is a tight structure, and the overall porosity of the UV protective knitted fabric is 60-75%; when the UV light intensity is greater than or equal to the threshold, both area A and area B are tight structures, and the overall porosity of the UV protective knitted fabric is 40-50%; such a design can take into account both UV protection performance and wearing comfort (such as breathable and moisture permeability, etc.).

[0022] As described above, in the adaptive intelligent breathable UV protective knitted fabric, all the tight structures are independently selected from one of plain stitch, rib stitch, double-ply stitch and warp stitch (preferably plain stitch, rib stitch or double-ply stitch).

[0023] As described above, the adaptive intelligent breathing UV protective knitted fabric has a non-light responsive yarn with a fineness of 50-500D; the non-light responsive yarn is polyester yarn, cotton yarn, nylon yarn, polypropylene yarn or mixed yarn (preferably polyester yarn, nylon yarn, polypropylene yarn or mixed yarn).

[0024] As described above, in an adaptive intelligent breathing UV protective knitted fabric, the fineness of the non-light-responsive yarn is greater than the fineness of the light-responsive yarn, which is conducive to weaving a tight structure in area B and a mesh structure in area A.

[0025] In actual use, the light intensity responded by the photoresponsive yarn must not be stronger than the upper limit of the light intensity that the human body can accept. Otherwise, the light intensity will cause damage to the human skin, but the mesh holes will not be closed and will not have a protective effect.

[0026] The present invention also provides a method for preparing the above-mentioned adaptive intelligent breathing UV protective knitted fabric. During knitting, non-photoresponsive yarn and photoresponsive yarn are knitted using a weft knitting machine or a warp knitting machine until the knitting length reaches the required length, thereby obtaining the adaptive intelligent breathing UV protective knitted fabric.

[0027] The steps of weaving by weft knitting machine are as follows:

[0028] (1) The non-photoresponsive yarn is knitted on a weft knitting machine in n rows, and the non-photoresponsive yarn is in a loop state at each position in the same row, so that a compact structure can be formed. The compact structure is obtained by looping any weave pattern that can make the yarns tightly arranged, n ≥ 1;

[0029] (2) Under the condition that the intensity of ultraviolet light is less than the threshold, the photoresponsive yarn and the non-photoresponsive yarn are woven together on the knitting machine for m rows. At one part of the same horizontal row, the photoresponsive yarn is in a looped state, and the non-photoresponsive yarn is in a tucked state. At another part of the same horizontal row, the photoresponsive yarn is in a floating or tucked state, and the non-photoresponsive yarn is in a looped state. Since the photoresponsive yarn does not form a loop at the position where it should form a loop, but floats or tucks, the original non-photoresponsive yarn does not withdraw from the needle hook, and the loop of the non-photoresponsive yarn in the previous horizontal row is stretched, so that the stretched loop of the non-photoresponsive yarn is consistent in height with the loop of the photoresponsive yarn in this horizontal row. At the same time, since the photoresponsive yarn is thinner than the non-photoresponsive yarn, holes appear at the loop of the photoresponsive yarn, that is, a mesh structure. The floating or tucked part of the photoresponsive yarn is still a tight structure, m≥1;

[0030] (3) Repeat steps (1) and (2) until the knitting length reaches the requirement, thereby obtaining the adaptive intelligent breathing UV protective knitted fabric.

[0031] The steps of weaving by warp knitting machine are as follows:

[0032] (1) On a warp knitting machine, a non-light-responsive yarn is first used to perform a warp flat yarn laying motion on the first combing bar (GB1) by using a process of passing n and leaving m, and a warp pile and warp bias yarn laying motion is performed on the second combing bar (GB2) by using a process of passing n and leaving m, so that holes are formed in areas lacking transverse extension lines and a compact fabric is formed in areas with transverse extension lines; wherein m ≥ 1, n ≥ 1;

[0033] (2) Under the condition that the UV intensity is less than the threshold, the photoresponsive yarn is inserted into the third comb bar (GB3) in the process of threading m and empty n, corresponding to the non-photoresponsive yarn on the first comb bar, the yarn is threaded empty at the fully threaded position and fully threaded at the empty position, forming a woven distribution of the photoresponsive yarn around the eyelet;

[0034] (3) The first comb bar, the second comb bar, and the third comb bar are laid in sequence according to the pattern laying rules;

[0035] (4) Using a warp knitting machine to weave into loops;

[0036] (5) Repeat steps (3)-(4) until the knitting length reaches the requirement, thereby obtaining the adaptive intelligent breathing UV protective knitted fabric.

[0037] As the preferred technical solution:

[0038] As described above, the method adopts a constant tension active yarn feeding method during the weaving process. The extensibility of the light-responsive yarn is greater than that of the non-light-responsive yarn, so the yarn must be actively fed during the weaving process, otherwise the light-responsive yarn will be stretched and affect the mesh effect; the weaving process parameters include: bending depth 2-10mm, coil length 5-20mm, and weaving tension 5-30cN; the present invention regulates the bending depth, yarn feeding amount and tension according to the design of the yarn and tissue structure, thereby achieving a smooth cloth surface effect.

[0039] Beneficial effects:

[0040] The adaptive intelligent breathing UV protection knitted fabric provided by the present invention, through the weaving arrangement of yarns and the design of the fabric structure, weaves light-responsive yarns that undergo macroscopic deformation under ultraviolet light together with non-light-responsive yarns, so that when there is no ultraviolet light or the ultraviolet light intensity is low, it has a mesh structure, thereby achieving the purpose of breathability. When the ultraviolet light intensity is high, the ultraviolet light is absorbed and converted into mechanical energy to achieve macroscopic deformation, and the mesh structure becomes a tight structure, thereby achieving the purpose of blocking ultraviolet light. The fabric part that is not directly exposed to ultraviolet light still has a mesh structure and still has a breathable effect. Ultimately, while protecting against ultraviolet light, the breathability of the knitted fabric is adjusted by changing the mesh size, thereby improving the wearing comfort of the knitted fabric. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 Schematic diagram of deformation of the light-responsive yarn of the present invention;

[0042] Figure 2 Schematic diagram of the organizational structure of the adaptive intelligent breathing UV protection knitted fabric of the present invention; in the figure, × represents a compact structure woven by non-photoresponsive yarns, √ represents a mesh structure woven by photoresponsive yarns, Indicates the number of cycles;

[0043] Figure 3 Schematic diagram of a single mesh structure of the adaptive intelligent breathing UV-protective knitted fabric of the present invention; in the figure, – represents a floating yarn, × represents a loop, √ represents a tuck, 1 represents a non-photoresponsive yarn, and 2 represents a photoresponsive yarn; in the figure, the black framed area represents the mesh structure woven with the photoresponsive yarn;

[0044] Figure 4 Schematic diagram of the tissue coil of the adaptive intelligent breathing UV protection knitted fabric of the present invention; in the figure, the black framed area is a single area A;

[0045] Figure 5 Schematic diagram of the deformation of the adaptive intelligent breathing UV protection knitted fabric of the present invention in response to light; in the figure, a is a schematic diagram of the adaptive intelligent breathing UV protection knitted fabric when the UV light intensity is less than a threshold value, and b is a schematic diagram of the adaptive intelligent breathing UV protection knitted fabric when the UV light intensity is greater than or equal to the threshold value;

[0046] Figure 6 Schematic diagram of yarn laying and yarn threading for preparing an adaptive intelligent breathing UV protective knitted fabric in Example 5 of the present invention; in the figure, a is a yarn laying motion diagram of the first combing bar, b is a yarn laying motion diagram of the second combing bar, c is a yarn laying motion diagram of the third combing bar, d is a yarn threading diagram of the first combing bar, e is a yarn threading diagram of the second combing bar, and f is a yarn threading diagram of the third combing bar;

[0047] Figure 7 Schematic diagram of the tissue coils of the adaptive intelligent breathing UV protection knitted fabric prepared in Example 5 of the present invention; in the figure, gray represents the non-light-responsive yarn knitting area, black represents the light-responsive yarn knitting area, and the black-framed positions are the mesh positions;

[0048] Figure 8 Schematic diagram of the deformation of the adaptive intelligent breathing UV protection knitted fabric produced in Example 5 of the present invention in response to light; in the figure, a is a schematic diagram of the adaptive intelligent breathing UV protection knitted fabric when the UV light intensity is less than a threshold value, and b is a schematic diagram of the adaptive intelligent breathing UV protection knitted fabric when the UV light intensity is greater than or equal to the threshold value;

[0049] Figure 9 Schematic diagram of yarn laying and yarn threading for preparing an adaptive intelligent breathing UV protective knitted fabric in Example 6 of the present invention; in the figure, a is a yarn laying motion diagram of the first combing bar, b is a yarn laying motion diagram of the second combing bar, c is a yarn laying motion diagram of the third combing bar, d is a yarn threading diagram of the first combing bar, e is a yarn threading diagram of the second combing bar, and f is a yarn threading diagram of the third combing bar;

[0050] Figure 10 The curve of the actuation strain of the photoresponsive yarn changing with light intensity. DETAILED DESCRIPTION

[0051] Below in conjunction with specific embodiment, further set forth the present invention.Should be understood that these embodiments are only used to illustrate the present invention and are not used in limiting the scope of the present invention.In addition, should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms fall equally within the scope limited by the appended claims of the application.

[0052] Example 1

[0053] A method for preparing an adaptive and intelligently breathing UV-protective knitted fabric comprises the following steps:

[0054] (1) Preparation of raw materials;

[0055] Light-responsive yarn: Liquid crystal elastomer yarn with a threshold of 175 mW / m 2 When the UV intensity changes from less than the threshold to greater than or equal to the threshold, the length decreases; when the UV intensity changes from greater than or equal to the threshold to less than the threshold, the length increases; when the UV intensity is less than the threshold, the fineness is 50D;

[0056] Non-photoresponsive yarn: nylon yarn, 100D fineness;

[0057] (2) 8 rows of non-photoresponsive yarn were knitted on a knitting machine, e.g. Figure 3 As shown, the non-light-responsive yarns at various positions in the same horizontal row are all in a looped state; wherein the weave structure is a plain weave;

[0058] (3) Under the condition that the UV intensity is less than the threshold, the photoresponsive yarn and the non-photoresponsive yarn are knitted together on a knitting machine for one row, such as Figure 3 As shown, in the same horizontal row, the state of the light-responsive yarn is float-float-loop-loop-loop-float-float-tuck-tuck, and the state of the non-light-responsive yarn is loop-loop-tuck-tuck-tuck-loop-loop-loop-loop; wherein, the weave structure is plain stitch;

[0059] During the weaving process of steps (2)-(3), a constant tension active yarn feeding method is adopted, and the weaving process parameters include: yarn bending depth 5mm, one coil length 10mm, and weaving tension 20cN;

[0060] (4) Repeat steps (2) and (3) until the knitting length reaches the requirement, thereby obtaining the adaptive intelligent breathing UV protective knitted fabric.

[0061] The final self-adaptive intelligent breathing UV protection knitted fabric (its tissue coils are as follows Figure 4 As shown), it consists of region A and region B; region A is a region woven from light-responsive yarns (as shown Figure 4 The black boxed area is one of the regions A); region B is the region woven by non-photoresponsive yarns;

[0062] When the intensity of ultraviolet light (band 275-400nm) is less than the threshold, the adaptive intelligent breathing ultraviolet protection knitted fabric (such as Figure 5 The overall porosity of the fabric (shown in a) is 60%. The organizational structure of region A is a mesh structure with an equivalent circular diameter of 2 mm. In the mesh structure, the driving tension between the light-responsive yarn and the surrounding coil is 15 cN. The organizational structure of region B is a tight structure. In the entire adaptive intelligent breathing UV protective knitted fabric, the distribution density of region A is 9×10 4 pcs / m 2 ;

[0063] When the intensity of ultraviolet light (band 275-400nm) is greater than or equal to the threshold, the adaptive intelligent breathing ultraviolet protection knitted fabric (such as Figure 5 The overall porosity of (shown in b) is 47-50%, the organizational structure of region A is a compact structure, and the organizational structure of region B is a compact structure.

[0064] Example 2

[0065] A method for preparing an adaptive and intelligently breathing UV-protective knitted fabric comprises the following steps:

[0066] (1) Preparation of raw materials;

[0067] Photoresponsive yarn: MXene / PDMS yarn with a threshold of 125 mW / m 2 When the UV intensity changes from less than the threshold to greater than or equal to the threshold, the length decreases; when the UV intensity changes from greater than or equal to the threshold to less than the threshold, the length increases; when the UV intensity is less than the threshold, the fineness is 30D;

[0068] Non-photoresponsive yarn: polyester yarn, fineness is 100D;

[0069] (2) 10 rows of knitting are performed on a knitting machine using non-photoresponsive yarn, wherein the non-photoresponsive yarn is in a looped state at each position in the same horizontal row; wherein the weave structure is a plain stitch;

[0070] (3) Under the condition that the ultraviolet light intensity is less than a threshold value, the photoresponsive yarn and the non-photoresponsive yarn are knitted together on a knitting machine for two rows. In the same horizontal row, the state of the photoresponsive yarn is float-float-loop-loop-loop-float-float-tuck-tuck, and the state of the non-photoresponsive yarn is loop-loop-tuck-tuck-tuck-loop-loop-loop-loop; wherein the weave structure is a plain stitch.

[0071] During the weaving process of steps (2)-(3), a constant tension active yarn feeding method is adopted; the weaving process parameters include: yarn bending depth 2mm, one coil length 5mm, and weaving tension 5cN;

[0072] (4) Repeat steps (2) and (3) until the knitting length reaches the requirement, thereby obtaining the adaptive intelligent breathing UV protective knitted fabric.

[0073] The final self-adaptive intelligent breathing UV protective knitted fabric consists of region A and region B;

[0074] Region A is the area woven by light-responsive yarn; Region B is the area woven by non-light-responsive yarn;

[0075] When the intensity of ultraviolet light (band 275-400nm) is less than the threshold, the overall porosity of the adaptive intelligent breathing UV protective knitted fabric is 70%, the organizational structure of region A is a mesh structure, the equivalent circle diameter of the mesh structure is 2mm, and the driving tension between the light-responsive yarn and the surrounding coils in the mesh structure is 5cN. The organizational structure of region B is a tight structure. In the entire adaptive intelligent breathing UV protective knitted fabric, the distribution density of region A is 6×10 4 pcs / m 2 ;

[0076] When the intensity of ultraviolet light (band 275-400nm) is greater than or equal to the threshold, the overall porosity of the adaptive intelligent breathing ultraviolet protective knitted fabric is 45-50%, the tissue structure of area A is a compact structure, and the tissue structure of area B is a compact structure.

[0077] Example 3

[0078] A method for preparing an adaptive and intelligently breathing UV-protective knitted fabric comprises the following steps:

[0079] (1) Preparation of raw materials;

[0080] Light-responsive yarn: Shape memory polymer yarn with a threshold of 225 mW / m 2 When the UV intensity changes from less than the threshold to greater than or equal to the threshold, the length decreases; when the UV intensity changes from greater than or equal to the threshold to less than the threshold, the length increases; when the UV intensity is less than the threshold, the fineness is 20D;

[0081] Non-photoresponsive yarn: polyester-cotton blended yarn (polyester content is 65wt%), fineness is 50D;

[0082] (2) knitting one row on a knitting machine using a non-photoresponsive yarn, wherein the non-photoresponsive yarn is in a looped state at each position in the same horizontal row; wherein the weave structure is a rib weave;

[0083] (3) Under the condition that the ultraviolet light intensity is less than a threshold value, the photoresponsive yarn and the non-photoresponsive yarn are knitted together on a knitting machine for one row. In the same horizontal row, the state of the photoresponsive yarn is float-float-loop-loop-loop-float-float-tuck-tuck, and the state of the non-photoresponsive yarn is loop-loop-tuck-tuck-tuck-loop-loop-loop-loop; wherein the weave is a plain stitch.

[0084] The knitting process of steps (2)-(3) adopts a constant tension active yarn feeding method; the knitting process parameters include: bending depth 5mm, one coil length 11mm, knitting tension 10cN

[0085] (4) Repeat steps (2) and (3) until the knitting length reaches the requirement, thereby obtaining the adaptive intelligent breathing UV protective knitted fabric.

[0086] The final self-adaptive intelligent breathing UV protective knitted fabric consists of region A and region B;

[0087] Region A is the area woven by light-responsive yarn; Region B is the area woven by non-light-responsive yarn;

[0088] When the intensity of ultraviolet light (band 275-400nm) is less than the threshold, the overall porosity of the adaptive intelligent breathing UV protective knitted fabric is 75%, the organizational structure of region A is a mesh structure, the equivalent circle diameter of the mesh structure is 1mm, and the driving tension between the light-responsive yarn and the surrounding coil in the mesh structure is 15cN. The organizational structure of region B is a tight structure. In the entire adaptive intelligent breathing UV protective knitted fabric, the distribution density of region A is 12×10 4 pcs / m 2 ;

[0089] When the intensity of ultraviolet light (band 275-400nm) is greater than or equal to the threshold, the overall porosity of the adaptive intelligent breathing ultraviolet protective knitted fabric is 43-48%, the tissue structure of area A is a compact structure, and the tissue structure of area B is a compact structure.

[0090] Example 4

[0091] A method for preparing an adaptive and intelligently breathing UV-protective knitted fabric comprises the following steps:

[0092] (1) Preparation of raw materials;

[0093] Light-responsive yarn: Liquid crystal elastomer yarn with a threshold of 175 mW / m 2 When the UV intensity changes from less than the threshold to greater than or equal to the threshold, the length decreases; when the UV intensity changes from greater than or equal to the threshold to less than the threshold, the length increases; when the UV intensity is less than the threshold, the fineness is 50D;

[0094] Non-photoresponsive yarn: polypropylene yarn, 300D fineness;

[0095] (2) 14 rows of knitting are performed on a knitting machine using non-photoresponsive yarn, wherein the non-photoresponsive yarn is in a looped state at each position in the same horizontal row; wherein the weave structure is a double-ply weave;

[0096] (3) Under the condition that the ultraviolet light intensity is less than a threshold value, the photoresponsive yarn and the non-photoresponsive yarn are knitted together for two rows on a knitting machine. In the same horizontal row, the state of the photoresponsive yarn is float-float-loop-loop-loop-float-float-tuck-tuck, and the state of the non-photoresponsive yarn is loop-loop-tuck-tuck-tuck-loop-loop-loop-loop; wherein the weave is a plain stitch.

[0097] The knitting process of steps (2)-(3) adopts a constant tension active yarn feeding method; the knitting process parameters include: bending depth 8mm, one coil length 16mm, knitting tension 20cN

[0098] (4) Repeat steps (2) and (3) until the knitting length reaches the requirement, and the self-adaptive intelligent breathing UV protection knitted fabric (its structure is as follows) is obtained. Figure 2 shown).

[0099] The final self-adaptive intelligent breathing UV protective knitted fabric consists of region A and region B;

[0100] Region A is the area woven by light-responsive yarn; Region B is the area woven by non-light-responsive yarn;

[0101] When the intensity of ultraviolet light (band 275-400nm) is less than the threshold, the overall porosity of the adaptive intelligent breathing UV protective knitted fabric is 60%, the organizational structure of region A is a mesh structure with a mesh diameter of 5mm. In the mesh structure, the driving tension between the light-responsive yarn and the surrounding coil is 20cN. The organizational structure of region B is a tight structure. In the entire adaptive intelligent breathing UV protective knitted fabric, the distribution density of region A is 2×10 4 pcs / m 2 ;

[0102] When the intensity of ultraviolet light (band 275-400nm) is greater than or equal to the threshold, the overall porosity of the adaptive intelligent breathing ultraviolet protective knitted fabric is 43-46%, the tissue structure of area A is a compact structure, and the tissue structure of area B is a compact structure.

[0103] Example 5

[0104] A method for preparing an adaptive and intelligently breathing UV-protective knitted fabric comprises the following steps:

[0105] (1) Preparation of raw materials;

[0106] Light-responsive yarn: Liquid crystal elastomer yarn with a threshold of 175 mW / m 2 When the UV intensity changes from less than the threshold to greater than or equal to the threshold, the length decreases; when the UV intensity changes from greater than or equal to the threshold to less than the threshold, the length increases; when the UV intensity is less than the threshold, the fineness is 100D;

[0107] Non-photoresponsive yarn: polyester yarn, 500D;

[0108] (2) On a warp knitting machine, a non-light-responsive yarn is first used to perform a warp flat yarn laying motion on the first comb bar by using a process of passing n and m, and then a warp pile and warp bias yarn laying motion is performed on the second comb bar by using a process of passing n and m, so that holes are formed in the area without transverse extension lines and a compact fabric is formed in the area with transverse extension lines; wherein n is 6 and m is 1;

[0109] (3) Under the condition that the UV intensity is less than the threshold, the photoresponsive yarn is threaded into the third comb bar in the process of threading m and empty n, corresponding to the non-photoresponsive yarn on the first comb bar, the yarn is threaded empty at the fully threaded position and fully threaded at the empty position, forming a woven distribution of the photoresponsive yarn around the eyelet;

[0110] (4) The first comb, the second comb, and the third comb are arranged as follows: Figure 6 The yarn laying motion diagram shown is to lay yarn in sequence;

[0111] (5) Using a warp knitting machine to weave into loops;

[0112] During the weaving process of steps (2) to (5), a constant tension active yarn feeding method is adopted, and the weaving process parameters include: yarn bending depth 10 mm, one coil length 20 mm, and weaving tension 30 cN;

[0113] (6) Repeat steps (4)-(5) until the knitting length reaches the requirement, thereby obtaining the adaptive intelligent breathing UV protective knitted fabric.

[0114] The final self-adaptive intelligent breathing UV protection knitted fabric (its tissue coils are as follows Figure 7 As shown) consists of area A and area B;

[0115] Region A is the area woven by light-responsive yarn; Region B is the area woven by non-light-responsive yarn;

[0116] When the intensity of ultraviolet light (band 275-400nm) is less than the threshold (adaptive intelligent breathing ultraviolet protection knitted fabric such as Figure 8As shown in (a), the overall porosity of the adaptive intelligent breathing UV protective knitted fabric is 60%. The organizational structure of region A is a mesh structure with a mesh diameter of 1 mm. In the mesh structure, the driving tension between the light-responsive yarn and the surrounding coil is 25 cN. The organizational structure of region B is a tight structure. In the entire adaptive intelligent breathing UV protective knitted fabric, the distribution density of region A is 1×10 4 pcs / m 2 ;

[0117] When the intensity of ultraviolet light (band 275-400nm) is greater than or equal to the threshold (adaptive intelligent breathing ultraviolet protection knitted fabric such as Figure 8 As shown in (b), the overall porosity of the adaptive intelligent breathing UV protective knitted fabric is 40-45%, the tissue structure of area A is a compact structure, and the tissue structure of area B is a compact structure.

[0118] Example 6

[0119] A method for preparing an adaptive and intelligently breathing UV-protective knitted fabric comprises the following steps:

[0120] (1) Preparation of raw materials;

[0121] Light-responsive yarn: Liquid crystal elastomer yarn with a threshold of 175 mW / m 2 When the UV intensity changes from less than the threshold to greater than or equal to the threshold, the length decreases; when the UV intensity changes from greater than or equal to the threshold to less than the threshold, the length increases; when the UV intensity is less than the threshold, the fineness is 100D;

[0122] Non-photoresponsive yarn: polyester yarn, 500D;

[0123] (2) On a warp knitting machine, a non-light-responsive yarn is first used to perform a warp flat yarn laying motion on the first comb bar by using a process of passing n and m, and a warp pile and warp bias yarn laying motion is performed on the second comb bar by using a process of passing n and m, so that holes are formed in the area without transverse extension lines and a compact fabric is formed in the area with transverse extension lines; wherein n is 1 and m is 1;

[0124] (3) Under the condition that the UV intensity is less than the threshold, the photoresponsive yarn is threaded into the third comb bar in the process of threading m and empty n, corresponding to the non-photoresponsive yarn on the first comb bar, the yarn is threaded empty at the fully threaded position and fully threaded at the empty position, forming a woven distribution of the photoresponsive yarn around the eyelet;

[0125] (4) The first comb, the second comb, and the third comb are arranged as follows: Figure 9 The yarn laying motion diagram shown is to lay yarn in sequence;

[0126] (5) Using a warp knitting machine to weave into loops;

[0127] The knitting process of steps (2) to (5) adopts a constant tension active yarn feeding method; the knitting process parameters include: bending depth 10mm, one coil length 20mm, knitting tension 30cN

[0128] (6) Repeat steps (4)-(5) until the knitting length reaches the requirement, thereby obtaining the adaptive intelligent breathing UV protective knitted fabric.

[0129] The final self-adaptive intelligent breathing UV protective knitted fabric consists of region A and region B;

[0130] Region A is the area woven by light-responsive yarn; Region B is the area woven by non-light-responsive yarn;

[0131] When the intensity of ultraviolet light (band 275-400nm) is less than the threshold, the overall porosity of the UV protective knitted fabric is 75%. The organizational structure of region A is a mesh structure with a mesh diameter of 2mm. In the mesh structure, the driving tension between the light-responsive yarn and the surrounding coil is 25cN. The organizational structure of region B is a tight structure. In the entire adaptive intelligent breathing UV protective knitted fabric, the distribution density of region A is 5×10 4 pcs / m 2 ;

[0132] When the intensity of ultraviolet light (wavelength range of 275-400 nm) is greater than or equal to a threshold value, the overall porosity of the ultraviolet protective knitted fabric is 45-50%, the tissue structure of region A is a compact structure, and the tissue structure of region B is a compact structure.

Claims

1. An adaptive intelligent breathing UV protection knitted fabric, characterized in that: The system includes region A, which is woven from light-responsive yarns. The length of the light-responsive yarns changes with the intensity of ultraviolet light, and thus the structure of region A changes with the intensity of ultraviolet light. When the intensity of ultraviolet light is less than a threshold, the structure of region A is a mesh structure. When the intensity of ultraviolet light is greater than or equal to the threshold, the structure of region A is a compact structure. The threshold value range is 125-225 mW / m 2 ; In the mesh structure, the driving tension between the photoresponsive yarn and the surrounding coil is no more than 30 cN; the mesh diameter or equivalent circle diameter of the mesh structure is 1-5 mm; when the ultraviolet light intensity changes from less than the threshold to greater than or equal to the threshold, the length of the photoresponsive yarn is shortened by 5%-50%; the area other than area A is area B, and area B is an area woven by non-photoresponsive yarn, and the organizational structure of area B is a tight structure.

2. The adaptive intelligent breathing UV protection knitted fabric according to claim 1, characterized in that: When the ultraviolet light intensity is less than a threshold value, the fineness of the photoresponsive yarn is 20-100D; the photoresponsive yarn is one or more of a photoresponsive liquid crystal elastomer yarn, a Mxene / PDMS yarn, and a shape memory polymer yarn.

3. The adaptive intelligent breathing UV protective knitted fabric according to claim 1, characterized in that: When the UV intensity is less than the threshold, the distribution density of area A in the entire UV protective knitted fabric is 10 4 -12×10 4 pcs / m 2 When the UV light intensity is less than the threshold value, the overall porosity of the UV protective knitted fabric is 60-75%; when the UV light intensity is greater than or equal to the threshold value, the overall porosity of the UV protective knitted fabric is 40-50%.

4. The adaptive intelligent breathing UV protection knitted fabric according to claim 1, characterized in that: All the tight structures are independently selected from one of plain stitch, rib stitch, double-purl stitch and warp stitch.

5. The adaptive intelligent breathing UV protection knitted fabric according to claim 1, characterized in that: The fineness of the non-light-responsive yarn is 50-500D; the non-light-responsive yarn is polyester yarn, cotton yarn, nylon yarn, polypropylene yarn or mixed yarn.

6. The adaptive intelligent breathing UV protective knitted fabric according to any one of claims 1 to 5, characterized in that: The fineness of the non-photoresponsive yarn is greater than that of the photoresponsive yarn.

7. A method for preparing the adaptive intelligent breathing UV protection knitted fabric according to claim 6, characterized in that: During knitting, non-light-responsive yarn and light-responsive yarn are knitted using a weft knitting machine or a warp knitting machine until the knitting length reaches the requirement, thereby obtaining an adaptive intelligent breathing UV protective knitted fabric; The steps of weaving by weft knitting machine are as follows: (1) The non-photoresponsive yarn is knitted n rows on a weft knitting machine, and the non-photoresponsive yarn is in a looped state at each position in the same horizontal row, n ≥ 1; (2) Under the condition that the UV intensity is less than the threshold, the photoresponsive yarn and the non-photoresponsive yarn are knitted together on a knitting machine for m rows. In a part of the same horizontal row, the photoresponsive yarn is in a looped state and the non-photoresponsive yarn is in a tucked state. In another part of the same horizontal row, the photoresponsive yarn is in a floating or tucked state and the non-photoresponsive yarn is in a looped state, m ≥ 1; (3) Repeat steps (1) and (2) until the knitting length reaches the required length, thereby obtaining an adaptive intelligent breathing UV protective knitted fabric; The steps of weaving by warp knitting machine are as follows: (1) On a warp knitting machine, a non-light-responsive yarn is first used to perform a warp flat yarn laying motion on the first comb bar by using a process of passing n and m, and then a warp pile and warp bias yarn laying motion is performed on the second comb bar by using a process of passing n and m, so that holes are formed in the area without transverse extension lines and a compact fabric is formed in the area with transverse extension lines; wherein m ≥ 1, n ≥ 1; (2) Under the condition that the UV intensity is less than the threshold, the photoresponsive yarn is inserted into the third comb bar in the process of threading m and empty n. Corresponding to the non-photoresponsive yarn on the first comb bar, the yarn is threaded empty at the fully threaded position and fully threaded at the empty position, forming a woven distribution of the photoresponsive yarn around the eyelet. (3) The first comb, the second comb, and the third comb are laid in sequence according to the pattern laying rules; (4) Using a warp knitting machine to weave into loops; (5) Repeat steps (3)-(4) until the knitting length reaches the requirement, and the adaptive intelligent breathing UV protective knitted fabric is obtained.

Images